Heated IV Bag

1
Heated IV Bag
University of Pittsburgh Senior Design BioE
1160/1161
Joe McFerron Ashley Danicic Justin Miller April
18, 2005 Mentor Linda Huckenstein, R.N
2
Outline

• Background
• Economic Considerations
• Problem Statement
• Design Description
• Human Factors Safety

• Experimental Methods
• Results
• Discussion
• Future
• Acknowledgements

3
Background

• Lavages are most frequently used to remove debris
  from an organ or cavity with repeated injections
  of solution.
• Saline solution is heated
• to increase circulation
• reduce risk of infection
• increase comfort of patient

4
Problem Statement

• There is no current device that attaches to the
  IV bag which controls and monitors the solution
  temperature
• There is currently no cost effective way to
  produce a device on a large scale
• Information from medical personnel
• Heated saline for lavage would be a desirable
  feature to incorporate

5
Problem Statement
Current Methods

• Microwave
• No temperature control
• PVC IV bag deforms at 135-180 degrees
• Temperature of solution decreases with time

• Heat Exchanger
• Bulky
• More expensive
• Needs internal pump in heat exchanger

6
Approximate Market (US)

• National Center for Health Statistics 2000
• 40 million inpatient, 31.5 million outpatient
  surgeries
• Ear Surgeries 878,000
• Nervous System Surgeries 2.2 million
• Nose, Mouth, and Pharynx Surgeries 2.36 million
• Cardiovascular System Surgeries 6.8 million
• Digestive System Surgeries 12 million
• Musculoskeletal System Surgeries 7.4 million
• Integumentary (Skin) System Surgeries 3.7
  million
• Of these 71.5 million surgeries,
• approximately 35.3 million were considered
  potential lavage situations

7
Design Description

• Functions
• Attaches to IV bag
• Control temperature of the solution
• Measure temperature of the solution
• Customer and Design Requirements

• Resistant to most liquids
• Accurate temperature control
• Adjust to fit various size bags
• Fast response

• Small
• Easy to assemble
• Easy to sterilize
• Flexible
• Cost effective

8
Design Description

• Materials Selected
• Etched Foil Heater -etched foil resistive element
  
• transfer heat more efficiently
• uniform heat patterns
• Kapton insulator
• Excellent dielectric strength
• Made for immersion in fluids
• Resistant to most acids, solvents, and bases

9
Design Description

• Temperature Controller
• Universal
• LED Display
• Accurately controls temperature
• 0.1 degree resolution
• Hysteresis control
• Thermocouple
• Platinum temperature sensing element
• Temperature range (-50oC to 155oC)
• Water resistant

10
Proposed Solution

• Heater
• Dimensions
• Actual 6.9 x 9
• Power
• Theoretical 290 W
• Actual 326 W
• Wraps around circumference of IV bag
• Heat solution quickly (lt10 min)

11
Power Estimation

• Based on these calculations
• P operating Pcd Pr Pcv
• P warm up mCp(Tf-Ti)/t
• t is 10 minutes
• It was determined that 290 W needed

12
Design Verification
Cross section of modeled bag after 11 min subject
to 300W
13
Competitive Analysis

• Strengths
• Price
• Heater (lt 50)
• Thermocouple (lt 15 )
• Temperature Controller ( lt 50)
• Adjust to different bag volumes
• No pressure pump needed
• Portable

• Weaknesses
• Inadequate insulation
• Possible uneven heat distribution
• No mixing

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Safety and Human Factors

• Safety
• Resistant to Liquids /
• Prevent Electric Shock
• Thermocouple immersion in water
• Heater water-proof
• Burn
• Insulator cool to touch
• Leakage
• Bag deformation from heat
• Leaching
• PVC IV bag
• PVC tubing

• Human factors
• Ease of assembly
• Ease of use
• Heater adjusts to changing volume of bag
• Protection from burn

15
Prototype


Thermofoil Heater
Temperature controller
Thermocouple
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How it works
Temperature Sensor feedback control
Temperature Controller
IV Bag
Heating Element
120 V
17
Experimental Methods

• Verification Testing
• Test Setup
• 1-liter Saline Bag
• Thermocouple placed 1cm from bottom of bag
• Heating element attached securely to bottom
  portion of bag
• Full power (120 V) used
• Recorded time-series of thermocouple

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Results

• Reached body temperature in 6.5 min
• Only 1oC fluctuation in temperature

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Results
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Criteria for Success
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Future

• Better method for thermocouple insertion
• IV port insertion
• Better method for attaching heater to bag
• Insulator added around heater to prevent (user)
  burn
• Customize circuitry to cut down on controller
  cost

22
Acknowledgements

• Drs. Hal Wrigley and Linda Baker
• Department of BioEngineering